1. Technical Field of the Invention
The present invention relates generally to the equipping and docking of aircraft, and, more particularly to the reloading and refueling of continuous flight unmanned aircraft systems.
2. Description of Related Art
The cargo transportation industry is crucial to the day-to-day functionality of our society as a whole. In order for goods to get from the manufacturer to the final point of destination, cargo must be shipped and transported via land, sea, or air. Every method has an associated means for transportation of such goods and an expense associated with such transportation means. One such means is air cargo transport. Various weapons are delivered on targets in time of war by manned aircraft or by unmanned guided weapons of various types. Development effort is currently being expended by the U.S. military toward development of unmanned combat aircraft that take off from airfields, deliver weapons on targets, and return to airfields for refueling and reloading of weapons. The unmanned combat aircraft require use of airfields and ground based support personnel.
Air cargo transport is currently facilitated by manned aircraft that land and take off from conventional airports. A significant element in operational cost of manned air cargo transport concerns the flight deck crew required for operation of the cargo aircraft and on-board provisions to support the flight crew. During long flights, expensive flight deck crews are often paid to spend many hours merely riding along with the aircraft flying with automatic controls. Eliminating the need for flight crews will decrease the overall operational expenditure and the cost of air cargo shipment. Although an unmanned cargo plane would seem to be an obvious solution, problems arise with considering unmanned aircraft. Landing and take-off of an unmanned aircraft presents problems in providing necessary communication links between ground controllers and the unmanned aircraft. Operation of unmanned aircraft from typical airports presents a potential safety problem to other aircraft and populated areas, thereby making conventional unmanned aircraft approaches for cargo shipment unattractive. Operation of unmanned aircraft from an airport or airbase also requires ground based personnel with special training in take-off, landing and ground support of unmanned aircraft.
Every time an unmanned aircraft needs to be recharged with supplies or fuel, there is an expense associated with the manpower necessary to assist and land such an aircraft. The same scenario holds true for take off of such an aircraft. Fuel utilization on take off and landing of a vehicle is inefficient in comparison with the utilization of fuel during flight. Landing of an unmanned aircraft presents additional problems in providing necessary communication links between ground controllers and the unmanned aircraft, particularly in combat situations or when the communication must cross enemy lines. Communications relay aircraft or satellites used for other communications must typically be utilized.
Communications relays and antennas typically must be located on towers or in orbiting satellites. Towers provide limited coverage because the curvature of the Earth limits lines of sight. Consequently large numbers of such towers are necessary to provide the desired coverage. The large number of towers presents an exploded operational expense. Orbiting satellites overcome the Earth""s curvature problems, however, they present problems of limited capacity per satellite and high expense for building and placing the satellite in orbit. If a satellite system fails, the time and expense involved in replacing a failed satellite can be exorbitant.
Previous attempts to use unmanned aircraft for air cargo or weapons transport have involved a need to periodically land the unmanned aircraft for fuel. Conventional in-flight refueling approaches present difficult problems for unmanned aircraft and increased danger to manned refueling aircraft. Maintaining the necessary relative locations for the tankers and unmanned aircraft for the duration of the fueling operations is difficult. Therefore the unmanned aircraft must land for refueling. In order for such an aircraft to land at a base, such a base must be equipped for ground handling, take-off and landing of unmanned aircraft. Such provisions must be available at any location in which unmanned aircraft are used. Unless ground controllers remain at the home base for unmanned combat aircraft, such controllers and their equipment must be deployed to forward locations to support aircraft operations. Such deployments present logistical problems in addition to problems of locating ground facilities for such deployments.
For military combat aircraft, personnel and equipment must be deployed to war theater airbases to support unmanned combat aircraft. Support personnel must be deployed to bases used by unmanned aircraft to refuel the aircraft and to reload or change weapons carried by the aircraft. The requirement to return to base between missions for refueling and reloading of weapons reduces the number of missions executable within a given time by each unmanned combat aircraft. Airbase use by unmanned aircraft presents problems similar to those found at conventional airports. Shared use of bases between manned and unmanned aircraft presents base capacity, safety and air traffic control problems.
Manpower and facility provisions necessary in both the civilian and military arenas provide an excessive expense to the operation of unmanned aircraft. Landings necessary to the utilization of unmanned aircraft are further complicated in the military arena where airbase traffic can become very heavy during time of war and where ground support personnel must be deployed. Therefore maintaining the aircraft in a situation of continuous flight addresses not only facility and personnel provisions but the issues of flight safety for manned aircraft operated from forward military airbases during time of war and combat availability of the manned aircraft for combat missions. There is, therefore, a need for an unmanned aircraft capable of operation over a long period of time without the need to land for the purposes of refueling and reloading of payloads.
The present invention achieves technological advances as an unmanned aircraft capable of continuous flight such that the problems of landing facilities and personnel are addressed and solved. Concern with untimely disclosure of information to an enemy is obviated by creating an aircraft capable of continuous flight.
A system consisting of an in-flight reloadable and in-flight refuelable continuously flying unmanned aircraft and a companion support aircraft enables the continuously flying unmanned aircraft to operate on a continuous basis without landing for either a series of military or commercial missions. The support aircraft is typically a much larger aircraft such as a wide body transport and may be either manned or unmanned. The support aircraft ferries and loads fuel, cargo, or weapons to the continuously flying unmanned aircraft. Both aircraft are specially configured to dock with each other during flight. In-flight refueling provisions are further included in both the continuously flying unmanned aircraft and the support aircraft to enable the support aircraft to refuel the continuously flying unmanned aircraft while it is docked with the support aircraft.
The present invention provides an unmanned aircraft able to operate over long periods of time and over a multiplicity of missions without need to land for the purposes of refueling or reloading of payloads. The unmanned aircraft is able to carry a multiplicity of different payloads within standard payload bay cartridges and such may be loaded and unloaded from a support aircraft during flight while the unmanned aircraft and the support ships are docked.
The present invention further provides a practical means for unmanned aircraft to dock and launch from support aircraft during flight.
The present invention also provides a means to transfer fuel from a support aircraft to unmanned aircraft while docked together during flight.
The present invention also provides a means to transfer fuel from the support aircraft to the unmanned aircraft while the unmanned aircraft is attached to extendable attachment devices of the support aircraft with these devices in the extended position.
The present invention also provides a means to remove the landing gear from the unmanned aircraft after takeoff, thus allowing the weight and space to be available for payloads.
The present invention also provides a means to extend and retract the landing gear of the unmanned aircraft while the unmanned aircraft is attached to extendable attachment devices of the support aircraft with these devices in the extended position.